U.S. patent number 4,752,465 [Application Number 07/005,597] was granted by the patent office on 1988-06-21 for aerosol foam.
This patent grant is currently assigned to Product Resources International, Inc.. Invention is credited to Leonard Mackles.
United States Patent |
4,752,465 |
Mackles |
* June 21, 1988 |
Aerosol foam
Abstract
A stable, edible anhydrous aerosol foam comprises a foamable
liquid oil, a foaming agent, a food grade propellant, and at least
15 wt % dispersed solid particles. The foam is a stable whip having
the consistency of whipped cream and can be dispensed in repeatable
and measurable quantities onto a spoon. It is useful to dispense a
wide variety of active, especially therapeutic, agents and, in
particular, as an alternative to tablets or capsules which are hard
to swallow or liquid medicines having a bad taste.
Inventors: |
Mackles; Leonard (New York,
NY) |
Assignee: |
Product Resources International,
Inc. (New York, NY)
|
[*] Notice: |
The portion of the term of this patent
subsequent to January 27, 2004 has been disclaimed. |
Family
ID: |
26674522 |
Appl.
No.: |
07/005,597 |
Filed: |
January 21, 1987 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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778026 |
Sep 20, 1985 |
4639367 |
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713294 |
Mar 18, 1985 |
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Current U.S.
Class: |
424/45;
514/945 |
Current CPC
Class: |
A61K
9/0056 (20130101); Y10S 514/945 (20130101) |
Current International
Class: |
A61K
9/00 (20060101); A61K 009/00 () |
Field of
Search: |
;424/45 ;514/945 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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933486 |
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Oct 1961 |
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GB |
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1121358 |
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Oct 1966 |
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GB |
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Primary Examiner: Schenkman; Leonard
Attorney, Agent or Firm: Amster, Rothstein &
Ebenstein
Parent Case Text
RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent
application Ser. No. 778,026, filed Sept. 20, 1985, now U.S. Pat.
No. 4,639,367 which is in turn a continuation-in-part of U.S.
patent application Ser. No. 713,294, filed Mar. 18, 1985, now
abandoned.
Claims
What is claimed is:
1. An edible, anhydrous aerosol foam composition comprising a
foamable liquid oil, a foaming agent, a propellant, and dispersed
solid particles, said propellant being present in an amount
sufficient to produce a stable, measurable foam but insufficient to
produce a spray when said composition is ejected through an aerosol
valve, and said dispersed solid particles being at least 15% by
weight of said composition.
2. The composition of claim 1 wherein said propellant comprises 1
to 10 wt. % of said composition.
3. The composition of claim 1 wherein said propellant is a
hydrocarbon.
4. The composition of claim 3 wherein said propellant is
propane.
5. The composition of claim 1 wherein said solid particles are
insoluble in the other ingredients of said foam composition.
6. The composition of claim 1 wherein the average size of said
solid particles is in the range of 50 to 100 microns.
7. The composition of claim 1 wherein said solid particles are
selected from the group consisting of powdered skim milk, crushed
nut solids, powdered flavors, sugars, sugarless sweeteners, and
clays.
8. The composition of claim 7 wherein said solid particles comprise
powdered sugar.
9. The composition of claim 1 wherein said solid particles comprise
an exothermic agent.
10. The composition of claim 1 wherein said foaming agent is
selected from the group consisting of lecithin, polyglycerol esters
of fatty acids having an HLB value of between 4.0 and 13.0,
glycerol esters of fatty acids having an HLB vaue of between 2.5
and 4.5, sorbitan esters of fatty acids having an HLB value of
between 3.0 and 7.0 and mixtures thereof.
11. The composition of claim 9 wherein said foaming agent comprises
2 to 40 wt. % of said composition.
12. The composition of claim 1 wherein said foaming agent is
substantially comprised of at least one water-dispersible
surfactant.
13. The composition of claim 1 wherein at least one of said liquid
oil and said solid particles comprises an active non-therapeutic
agent.
14. The composition of claim 1 wherein said liquid oil comprises an
active therapeutic agent.
15. The composition of claim 14 wherein said liquid oil is selected
from the group consisting of mineral oil, castor oil, fish liver
oils, fish body oils, and oil-soluble materials selected from the
group consisting of epinephrine, isoproterenol, phenylpropanolamine
base, ephedrine, amphetamine, dibucaine, dyclonine base, lidocaine,
chloral hydrate, benzyl benzoate, vitamins, and steroid
hormones.
16. The composition of claim 1 wherein said liquid oil is selected
from the group consisting of soybean oil, partially hydrogenated
soybean oil, linseed oil, corn oil, peanut oil, sunflower oil,
cottonseed oil, olive oil, liquid petrolatums, oleic acids, lauric
acids and mono- and diglyceride oils.
17. The composition of claim 1 wherein said propellant comprises 1
to 10 wt. % of said composition, said foaming agent comprises 2 to
40 wt. % of said composition, said solid particles comprise at
least 15 wt. % of said composition and are insoluble in the other
ingredients of said foam composition, and the balance of said
composition is said liquid oil.
18. As an article of manufacture, a pressurized aerosol container,
said container having therein an edible, anhydrous aerosol foam
composition comprising a foamable liquid oil, a foaming agent, a
propellant, said propellant being present in an amount sufficient
to produce a stable, measurable foam but insufficient to produce a
spray when said composition is ejected through an aerosol valve,
and at least 15% by weight of dispersed solid particles.
Description
BACKGROUND OF THE INVENTION
Tablets and capsules are the most common dosage forms for the oral
administration of nutritional, medicinal, or other therapeutic
products. It is well known, however, that these dosage forms are
unacceptable for use by people who have difficulty in swallowing
tablets and capsules and that the difficulty is exacerbated by
larger tablets and capsules and, in some instances, by the bad
taste of the medication. It is generally accepted that these types
of problems with medications are serious because they may lead to a
failure on the part of patients to comply with the medication
regimen ordered by the physician.
The common alternatives to conventional tablets and capsules are
chewable tablets and aqueous or hydroalcoholic liquids such as
syrups, suspensions and elixirs. Such dosage forms are commonly
used for analgesics, cough and cold medications, antibiotics,
vitamins and many other nutritional or medicinal products. In
general, these forms do not significantly improve the taste of a
medication or make it easier to swallow larger doses. For example,
therapeutic agents in either chewable tablet or suspension form are
generally disliked because they are gritty, astringent and leave an
unpleasant aftertaste. Oils, such as mineral oil, fish oils, cod
liver oil and castor oil, are usually taken in large doses and,
since they are greasy and unpleasant to take, some method must be
found to make them easier to ingest. In the past this problem has
been dealt with by encapsulating the oils in soft gelatin capsules
or by emulsifying the oils in oil-in-water emulsions. These
solutions have not been completely satisfactory.
The problem with encapsulation is that, since the maximum size soft
capsule that can be ingested contains only about one gram of oil,
the ingestion of many such capsules is required when the dose of
the oil is large. In the case of fish oil the dose is about five
grams a day or more, and the doses of cod liver oil, castor oil,
and mineral oil are even larger. The problem with emulsification is
that bottles of oil-in-water emulsions of oils are subject to
deterioration as a result of attack by microorganisms or oxidation
by the air to which they are continually exposed and thus have a
limited shelf life. Oils and oil-soluble active agents are
frequently vulnerable to oxidation. The integrity of oils, such as
fish oil containing Omega 3 fatty acids, and the vitamin potency
and unsaturated fatty acid character of oils, such as fish liver
oils, are all susceptible to attack by oxidation.
Although aerosol packaging has found high consumer acceptance in
many areas, including pharmaceutical products such as inhalants, it
has not heretofore been considered for use in formulations
requiring a high concentration of suspended solids, i.e., greater
than 5 to 13%, because a high solids content usually causes
malfunctioning of the aerosol valve. It is neither economical nor
practical to dispense active solid agents in the very dilute
formulations which would be required for dispensing through an
aerosol valve. Moreover, such dilute formulations usually produce
an uncontrollable and unmeasurable spray, thereby making it
difficult to control or measure the amount of the formulation being
dispensed. A further difficulty with aerosol packaging is that most
aqueous aerosol solutions would be unacceptable for dispensing
active solid agents because the dissolution of the active
ingredient prior to ingestion could reduce its bio-availability and
also produce an unpleasant taste.
British Pat. No. 1,121,358 discloses an aerosol foam composition
for dispensing an oral medication, but is specifically limited to
compositions which are oil-in-water emulsions. Furthermore, the
composition is either devoid of dispersed solid particles or
contains a very minimal solids content, less than one percent. It
is believed that the presence of water in the emulsion not only
reduces the ability of the composition to hold particulate solids,
but also introduces stability problems resulting in shorter shelf
life.
There are several prior art patents which presumably disclose
anhydrous aerosol foams. For example, U.S. Pat. No. 3,135,658
teaches a method of treating bovine mastitis with a medicated,
pressurized, self-propelling, milk-miscible oleaginous liquid
composition which foams only after it enters the udder and contacts
the natural foaming agents of the milk. It does not teach any type
of dosable or meterable foam. Furthermore, the composition is
inedible or at least unpalatable.
U.S. Pat. No. 3,770,648 discloses an anhydrous aerosol foam
composition for external use which incorporates a silicone resin in
a solution of organic solvents to produce a stable "quick breaking"
foam when the foam is rubbed into or spread over a surface on which
it has been deposited. This patent does not disclose any anhydrous
foam products which are suitable for ingestion. It also does not
teach any type of dosable or meterable foam for dispensing high
concentrations of solid therapeutic agents.
U.S. Pat. No. 3,849,580 discloses an aerosol dispensing system
which delivers non-aqueous butter-like edible fat compositions in a
foam form. These foams contain no foaming agent and are intended to
be used as food spreads.
U.S. Pat. No. 3,929,985 teaches a medicated aerosol foam
composition for introduction into the vagina for the treatment of
vaginitis, but the composition is devoid of any dispersed solid
particles and is inedible or at least unpalatable.
U.S. Pat. No. 4,425,164 teaches the preparation of an aerosol spray
cookware lubricant composition similar to the product which is
commercially available in food stores under the trademark "PAM".
This spray is formed from a mixture of a vegetable oil solution of
an emulsifier (lecithin) in admixture with at least 10%, preferably
20 to 30%, of a hydrocarbon propellant and up to 15%, preferably 3
to 10%, of suspended flour or starch particles. The resulting
product is a spray in which the particles serve as a visual
indicator that the spray is being uniformly applied to the cooking
surface. There is no disclosure or suggestion of a directly
ingestible stable foam product capable of yielding repeatable,
measurable quantities of an active agent from an aerosol
container.
Other disclosures of vegetable oil, lecithin-containing edible
aerosols (U.S. Pat. Nos. 4,188,412 and 3,821,007) also indicate
that such materials are sprays rather than foams. These patents
additionally teach that foaming action would be undesirable in such
a product.
U.S. Pat. No. 4,174,295 teaches the preparation of a pharmaceutical
aerosol containing glycerides or monostearates.
SUMMARY OF THE DISCLOSURE
It has now been found that a stable, edible, anhydrous aerosol foam
or whip capable of suspending up to 50% by weight of a dispersed
solid can be prepared from a foamable, edible anhydrous liquid oil;
a foaming agent; at least 15% by weight of dispersed solids; and
controlled amounts of a food grade propellant which are sufficient
to produce a stable foam rather than a spray. The foam, as
delivered from an aerosol canister, has the consistency of whipped
cream, is stable for extended periods and is hostile to the growth
of micro-organisms so that refrigeration is not required. It can be
safely ingested so that it is ideal as a carrier for active agents,
especially oily or oil-soluble medicines, vitamins, minerals or
other therapeutic agents. The foam of this invention assists in
masking the taste of bitter drugs, such as phenylpropanolamine
base, dyclonine base, steroids, etc. and making it easier to
administer large amounts of high dosage medications such as fish
oil supplements, castor oil and mineral oil. Such oils in a whip or
aerosol foam becomes extremely palatable and easy to swallow,
making it possible to prepare products containing a much larger
amount of active ingredients, so that greater effectiveness and
compliance can be achieved than is common with conventional
therapeutic forms. For example, a typical dose of fish oil
supplement is 6 one-gram soft gelatin capsules, whereas the foam of
the invention requires only 2 rounded teaspoonfuls to deliver the
same amount of active ingredient. Similar desirable results can be
achieved with antitussives such as dextromethorphan base,
antihistamines such as chlorpheniramine base, decongestants such as
pseudoephedrine base and local anesthetics such as benzocaine or
dyclonine base.
The stability of the novel foam formulation enables it to be
controlled in the sense that it can be measured on a spoon or a
similar device for oral administration, or measured into an
applicator for rectal or vaginal administration. Obviously, such a
foam is capable of being packaged in small, portable aerosol
containers (the size of a typical breath spray container) which may
be easily transported in a pocket or purse as well as in shaving
cream-sized containers for home use.
The stability of the whip or foam product also enables the present
invention to be utilized as a base for food products. Thus, it can
be combined with numerous sweetening and flavoring agents to
provide a whipped cream-type food product which needs no
refrigeration and no preservatives. Sweetening and flavoring
agents, of course, may also be employed to enhance the flavor of
pharmaceutical products to further enhance the likelihood of
patient compliance.
While not wishing to be limited to any particular theory, it is
believed that the formulations of the present invention are capable
of achieving the foregoing results without valve clogging due to a
novel combination of ingredients that produces a high viscosity
formulation capable of keeping the small solids particles dispersed
and of lubricating the aerosol valve.
In a preferred embodiment of the present invention, the propellant
comprises 1 to 10 wt. % of the composition, the foaming agent
comprises 2 to 40 wt. %, the solid particles comprise at least 15
wt. % and are insoluble in the other ingredients of the
composition, and the balance of the composition is the liquid
oil.
Typically the propellant is a hydrocarbon, preferably propane. The
foaming agent is selected from the group consisting of lecithin,
polyglycerol esters of fatty acids having an HLB
(hydrophilic/lipophilic balance) value of between 4.0 and 13.0,
glycerol esters of fatty acids having an HLB value of between 2.5
and 4.5, sorbitan esters of fatty acids having an HLB value of
between 3.0 and 7.0 and mixtures therof. The solid particles are
active agents selected from the group consisting of powdered skim
milk, crushed nut solids, powdered flavors, sugars, sugarless
sweeteners, and clays, with powdered sugar being a preferred solid
particle. The solid particles are insoluble in the other
ingredients of the foam composition and have an average size in the
range of 50 to 100 microns.
The liquid oil may be a non-therapeutic agent selected from the
group consisting of soybean oil, partially hydrogenated soybean
oil, linseed oil, corn oil, peanut oil, sunflower oil, cottonseed
oil, olive oil, liquid petrolatums, oleic acids, lauric acids and
mono- and diglyceride oils, or it may be an active therapeutic
agent selected from the group consisting of mineral oil, castor
oil, fish liver oils, fish body oils, and various oil-soluble
ingredients such as epinephrine, isoproterenol, phenylpropanolamine
base, ephedrine, amphetamine, dibucaine, dyclonine base, lidocaine,
chloral hydrate, benzyl benzoate, vitamins, and steroid
hormones.
The present invention also encompasses, as an article of
manufacture, a pressurized aerosol container, the container having
therein an edible, anhydrous aerosol foam composition. The
composition comprises a foamable liquid oil, a foaming agent and a
propellant, the propellant being present in an amount sufficient to
produce a stable, measurable foam but insufficient to produce a
spray when the composition is ejected through an aerosol valve, and
at least 15% by weight of dispersed solid particles.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The essential components of the present invention are:
1. A foamable, edible, anhydrous liquid oil.
2. A foaming agent (surfactant system).
3. At least a 15% concentration by weight of dispersed solids.
4. A food grade propellant.
THE LIQUID OIL
The liquid oil can be the sole active agent of the system, as in
the case of fish oil or mineral oil, or can be the carrier for an
oil-soluble active agent, as in the case of oil-soluble vitamins or
oil-soluble therapeutic agents. As used throughout the
specification, the term "oils" includes "oil-soluble active
agents".
The foamable, edible anhydrous liquid oils utilized in the present
invention are varied and of no great critical significance except
where they are themselves the active agents. Typical among the
edible organic oils useful for the present invention are those such
as soybean oil, partially hydrogenated soybean oil, vegetable oil,
linseed oil, corn oil, peanut oil, sunflower oil, cottonseed oil,
olive oil, liquid petrolatum, oleic acid, lauric acid, and mono-
and diglyceride oils. As indicated above, the basic criteria for a
liquid oil utilizable in the present invention is that it is
foamable and edible.
Typically, the edible oils utilized in the present invention are
present in the formulation in a percentage of 35 to 75% by weight
of the total composition. A preferred range is 45 to 70% by weight
of the total composition. The amount of oil may be varied based
upon the nature and amount of the other ingredients in the
formulation, such as the amount of dispersed solids. Ordinarily,
the percentage amount of each other ingredient in the formulation
is first selected, and the oil is the ingredient added to bring the
formulation to 100%.
The present invention provides a valuable delivery system for the
oral administration of oily medicinal agents such as the following:
mineral oil as a lubricant laxative, castor oil as an irritant
laxative, cod liver and other fish liver oils as natural sources of
vitamins A and D, fish body oils containing Omega 3 fatty acids as
blood cholesterol reducers for the prevention of heart attacks,
oil-soluble vitamins (such as vitamins A, D, E, and K), oil-soluble
therapeutic agents (such as steroid hormones, e.g. estradiol,
testosterone, progesterone, cortisone and hydrocortisone),
sympathomimetics (such as epinephrine, isoproterenol,
phenylpropanolamine, ephedrine, and amphetamine), anesthetics (such
as dibucaine, dyclonine, and lidocaine), sedatives (such as chloral
hydrate), anthelmintics (such as benzyl benzoate), and other
oil-soluble medicinal agents. The active pharmaceutical materials
in oil form which can be incorporated in the foam of the present
invention can be any of the common analgesics, antitussives,
laxatives, vitamins, minerals, or any other type of therapeutic
agent. Indeed, most therapeutic agents which are normally in a
water-soluble solid particle form (e.g., dyclonine,
phenylpropanolamine) can be converted to oil-soluble amine bases
and incorporated as such in the foams of the present invention.
In addition to serving as a vehicle for active agents for
therapeutic (including nutritional supplement) purposes, it has
been found that the systems of this invention can be used to
prepare excellent tasting food products. Food products that
normally require refrigeration, to prevent dry out and spoilage due
to air oxidation, can be prepared in this system with extended
shelf life, requiring no refrigeration or protection from the
atmosphere. Such shelf-stable food products having active oil
ingredients include dressings for salads and bread toppings (such
as peanut butter and garlic butter), dessert foam and mousse
toppings, coffee creamers, etc.
This novel system permits the preparation of unique products that
solve the significant problem of the stability of oils (or
oil-soluble active agents) that are vulnerable to oxidation. Since
oxygen can easily be excluded from the system in the aerosol can,
the integrity of oils such as fish oil containing Omega 3 fatty
acids can be preserved. Similarly, cod liver oil and other fish
liver oils can be maintained for long periods of time without loss
in vitamin potency or oxidation of their unsaturated fatty acids.
Oil-soluble vitamins can be dissolved in the oils in these systems
and their potency can be maintained over the shelf life of such
products.
THE FOAMING AGENT
Foaming agents utilizable in the present invention are selected
from the group consisting of lecithin and various polyol fatty acid
esters and mixtures thereof. Lecithin is the commercial name for a
class of naturally occurring compounds derived from soybeans. These
compounds are phosphatides and phospholipids. The principal
components of lecithin are a naturally occurring mixture of
phosphatidyl choline, phosphatidyl ethanolamine, inositol
phosphatides and related phosphorous containing lipids. Chemically,
lecithin is described as phosphatidyl choline and is a mixture of
the diglycerides of stearic, palmitic and oleic acids linked to the
choline ester of phosphoric acid. It is available commercially as a
60% solution in soybean oil or as a granular powder essentially
free of soybean oil. A hydroxylated lecithin, modified to increase
the hydrophilic properties is also commercially available. This
hydroxylated lecithin is commonly supplied as a 60% solution in
soybean oil.
The polyol fatty acid esters utilizable in the present invention
are commercial products and are comprised of three types:
1. Glycerol esters of fatty acids.
2. Polyglycerol esters of fatty acids.
3. Sorbitan esters of fatty acids.
The glycerol esters which have been found to be advantageous in
generating a suitable anhydrous edible aerosol foam are prepared by
standard esterification methods and have an HLB of between 2.5 and
4.5. Among the preferable glycerol fatty esters utilizable in the
present invention are those such as glycerol monostearate (HLB 3.2)
and glycerol monooleate (HLB 3.4).
The polyglycerol esters utilizable in the present invention are
commercial products prepared by first polymerizing glycerine under
alkaline conditions. The polymerization is controlled to yield the
particular desired average molecular weight. Investigations
indicate that the polymerization of glycerol progresses
predominately in a straight-chain manner. The esters are prepared
by reacting the polyglycerols with a specific fatty acid or by the
alcoholysis of a triglyceride. by this method, it is possible to
prepare esters ranging anywhere from hydrophilic monoesters such as
decaglycerol monolaurate to a lipophilic decaglycerol
decaoleate.
The polyglycerol esters preferably used in the present invention
have an HLB value of between 4.0 and 13.0. These have been found to
be most advantageous in generating a suitable anhydrous aerosol
foam. Among the preferable polyglycerol esters utilizable in the
present invention are those such as: hexaglycerol distearate (HLB
4.0), decaglycerol tetraoleate (HLB 6.0), triglycerol monostearate
(HLB 7.0), triglycerol monooleate (HLB 7.0), octaglycerol
monostearate (HLB 12.0) and octaglycerol monooleate (HLB 13.0).
The sorbitan fatty acid esters which have been found to be
advantageous in generating a suitable anhydrous edible aerosol foam
are commercial products prepared by standard esterification methods
and have an HLB of between 3.0 and 7.0. Among the preferable
sorbitan esters utilizable in the present invention are those such
as sorbitan monostearate (HLB 4.7), sorbitan monooleate (HLB 4.3),
and sorbitan monopalmitate (HLB 6.7).
Additionally, a combination of any of the polyol fatty acid esters
may be utilized in the present invention.
The polyol fatty acid esters are somewhat more hydrophilic than
lecithin so that their use allows the foamable, edible anhydrous
liquid oil to be more easily dispersed when contacted with an
aqueous medium. This gives a much less oily feel in the mouth and
releases the suspended medicament more rapidly in the stomach.
Additionally, they may be used in conjunction with lecithin in the
same system which causes the lecithin to become more hydrophilic
and therefore more palatable than the lecithin alone. This
combination also causes the release of an active agent--whether oil
or solid--faster in the stomach. As it is necessary for the final
product to be edible, the polyol esters are approved for internal
use by the Food and Drug Administration.
The foaming agent utilized in the present invention is present in
an amount of from 2 to 40% by weight. The amount of foaming agent
utilized depends upon the particular foaming agent being utilized,
the particular foamable, edible, anhydrous liquid oil being
utilized and the propellant system. A preferred range of foaming
agent is from about 3 to 15% by weight of the composition, with 10%
being especially preferred. It is a particularly desirable
additional feature of the foaming agents that they possess
surfactant properties and, therefore, affect the rate at which the
active ingredient of the foam--whether oil or dispersed solid--is
released in the mouth. Accordingly, some variations in the amount
of foaming agent in a particular formulation may be purposely
chosen based on the nature of the active ingredient in order to
control the rate of release.
THE PROPELLANT
The edible propellant can be selected from the class of
hydrocarbons that are gaseous under atmospheric pressures and
liquefy when compressed, or certain edible fluorocarbons such as
FREON 115. The most commonly used are propane, butane and
isobutane. Propane is approved for use in ingested products and can
be obtained commercially in an odorless and tasteless form which is
ideally suited for use in preparing the whip of the present
invention. Since these liquefied gases are soluble in the oil
vehicle of the composition, there is a resulting reduction in their
vapor pressure. Therefore, it is most advantageous to use propane
since it has the highest pressure of the three generally available
hydrocarbon propellants and, even when dissolved in the low
concentrations normally employed in this invention, produces a
product with a pressure of 30-40 pounds per square inch over
atmospheric pressure. This pressure is required to eject the foam
from the container and produce a stable, dense foam which can be
measured onto a spoon to facilitate administration. However, since
propane is soluble in the oil base, there is very little pressure
drop from the first to the last actuation of the aerosol valve and
a satisfactory foam is produced when each dose is expelled.
The amount of propellant used is critical since too much will
produce an undesirable spray rather than the desired stable,
measurable foam. Amounts of propellant in the range of from 1-10
wt. % are operative, but 3-5 wt. % is the preferred concentration
based upon the total weight of the contents of the aerosol
container. The amount of propellant used may vary somewhat,
depending upon the nature and amount of the other ingredients in
the composition but, in all cases, the lowest amount sufficient to
form a stable, measurable foam without forming an unmeasurable
spray will be selected.
Propellants other than the liquefied hydrocarbon gases can be used
including compressed gases like the edible fluorocarbons (e.g.,
Freon 115), nitrogen, nitrous oxide and carbon dioxide, although
they do not produce the most desirable foams over the life of the
product in use.
THE DISPERSED SOLIDS
A particularly important and surprising feature of the foams of
this invention is their ability to suspend high concentrations,
i.e., up to 50% by weight, of solids, and mask their taste upon
ingestion of the foam. Preferably, the suspended particles are
ground to a very fine particle size since this facilitates the
formation and maintenance of a uniform dispersion and prevents
clogging. Particle sizes in the range of 50 to 100 microns in
diameter are preferred.
The foam of the present invention will contain at least 15 wt. % of
suspended solid particles and can contain up to 50 wt. % of
suspended solid particles without any appreciable valve
malfunctioning. This ability to suspend high percentages of solids
without valve malfunctioning enables the aerosol foam system of the
present invention to be utilized for a wide variety of
formulations. The reasons for the unique ability of the foams to
suspend such a high concentration of solids without valve clogging
are not fully understood, but it is believed to result from a
combination of the small particle size, the high viscosity of the
foam formulation due to its low propellant content which aids in
keeping the particles dispersed and reduces agglomeration and
settling, and the lubricating effect of the oil on the valve.
These suspended solid particles serve to modify the taste
characteristics of the oil to make it less greasy and also serve to
make the foam more dense by their physical presence adding
substance to the foam. They also serve as foci for evaporation of
the propellant when exposed to the atmosphere upon expulsion from
the aerosol can. This makes the foam more dense and physically
stable in much the same way as meringues are made stable by beating
air into egg whites or whipped cream is made stable by beating air
into cream.
Powdered sugar is one of the preferred dispersed solids since it
provides good taste and mouth feel characteristics to the foam, in
addition to providing the beneficial physical effects described
above. Sugars other than sucrose (such as fructose) or "sugarless"
sweeteeners (such as sorbitol) can be employed. Other dispersed
solids can also be used such as powdered skim milk for coffee
creamers, the solids of crushed nuts (e.g., peanuts), clays (i.e.,
absorbents), lakes of colors (i.e., pigments), powdered flavors,
etc., depending upon the needs of the specific product formulation.
In all cases the particle size should be less than 100 microns to
prevent clogging the valves of the aerosol.
The system of this invention can be used to prepare excellent
tasting food products. Food products, such as whipped cream or
whipped toppings that normally require refrigeration to prevent dry
out or spoilage due to air oxidation, can be prepared in this
system with extended shelf life, requiring no refrigeration or
protection from the atmosphere. Such shelf-stable food products
include toppings for desserts and ice cream (e.g., chocolate mousse
or strawberry mousse) incorporating Bakers chocolate, vanillin
and/or cocoa powder as dispersed solids, coffee or hot drink
creamers (e.g., for instant cappuccino) incorporating powdered
non-fat milk and titanium dioxide as dispersed solids, spreads
(such as peanut butter) incorporating crushed nut solids as
dispersed solids, etc.
The dispersed solids may be an adsorbent such as clay; for example,
the clay adsorbent available under the mark Veegum F (composed of
magnesium and aluminum silicates). Such adsorbents complex the
distasteful active ingredients, such as phenylpropanolamine base or
dextromethomorphan base, on their surface and prevent them from
contacting the tastebuds of the mouth. The clays are especially
useful in conjunction with other dispersed solids, such as sugars,
which mask any residual taste of the distasteful ingredients.
The dispersed solids may be an exothermic agent such as anhydrous
sodium aluminosilicate (commercially available under the name
Valfor 950). Upon exposure to water the exothermic agent undergoes
a heat-producing reaction capable of warming up the dispensed foam.
A foam containing such an exothermic agent may find utility in a
therapeutic setting where the heat may enhance the absorption of
therapeutic agents in the foam by the body or simply as a
self-heating massage lotion. While the useful exothermic agents are
not particularly pleasant tasting, the composition can be given an
acceptable taste through the use of sugars, flavorings, and the
like as taught herein. The exothermic agent may be employed in a
hot oil anti-dandruff mousse so that the application of the foam to
wet hair generates heat, which promotes the penetration of the oils
into the dandruff layers on the scalp, thereby aiding in their
removal upon subsequent rinsing. The object in such a case is not
to produce a particularly enjoyable flavor, but simply to provide a
composition which is safe in the event that some of the mousse
accidently enters the user's mouth and which is of generally
tolerable taste such that the user does not have a strongly
negative reaction to the taste.
GENERAL
The oily or greasy mouthfeel of the oils can be minimized and
largely eliminated, so that the final taste of the product can be
very pleasant, by the three other essential components of this
unique system. The first method of reducing oiliness in the mouth
is provided by the high concentrations of dispersed solids which
the system of this invention can tolerate, and indeed requires.
This effect is analogous to the taste difference that exists
between shortening which is greasy and cake icing which is
pleasant. The difference is that, in the case of icing, the
shortening is mixed with large amounts of powdered sugar so that,
when ingested, the sugar dissolves in the mouth and dilutes the
greasy effect of the shortening. In the system of this invention
large concentrations of sugar can be mixed with the oils to provide
the same effect in the mouth.
The second method of reducing oiliness in the mouth is provided by
the foaming agent, which is one or more edible surfactants. Since
these surfactants modify the oils to make them more
water-dispersible, it has been found that the system becomes more
dispersible in the aqueous fluids in the mouth and this further
reduces the greasy mouthfeel the oils normally possess. And since
we have found that it is possible to adjust this effect by
increasing the water-dispersibility of the surfactant system, an
even greater reduction in greasiness in the mouth can be
effected.
The third method of reducing oiliness in the mouth is provided by
the edible propellant, which is an essential component of the
system. Since the propellant causes the composition to expand and
foam when it is expelled from the aerosol can, the density of the
product is greatly reduced. In fact the density changes from about
1.0 g/cc in the can to about 0.25 g/cc when the foam is formed upon
expulsion from the can. This fourfold reduction in density (or
increase in volume for a given weight of product) provides a
further dilution of the oil in the product so that greasiness is
even further reduced upon ingestion.
Thus the system provides three ways to reduce oiliness or
greasiness of oils upon ingestion--dispersed solids to overcome the
flavor of the oily taste, surfactants to disperse the oil in the
mouth, and propellant to reduce the density of the oil.
Since the system of this invention is completely anhydrous, it
provides a very poor medium for the growth of microorganisms. And
if sugar is used as one or all of the dispersed solids, it has been
found that the system is actively bactericidal. This surprising
effect was discovered when formulations of this invention were
deliberately inoculated with aqueous suspensions of microorganisms.
It was expected that these organisms would not grow in the medium
of the product. But it was found that the organisms were killed in
the product, even though no chemical preservative was present. This
effect was found with all the organisms used, even pathogenic
anaerobes like Clostridium which could be expected to remain viable
in systems where air was excluded. The system of this invention was
found to be cidal in these organisms so that within a week the
number of organisms present was reduced to substantially zero. This
cidal effect means that contamination by microorganisms during the
manufacture of this product is unlikely. In addition, the product
that remains in the spout of the aerosol can during use by the
consumer will not be contaminated by organisms from the
environment.
It will be appreciated that the present invention includes systems
in which the active ingredient is either an oil or a dispersed
solid, and the active agent, if also therapeutic, is an oil. This
system thus permits the formulation of both oils (including
oil-soluble materials) and solids as active agents into products
that are stable when on the shelf, stable during use by the
consumer, and pleasant to take when ingested.
The foams of the present invention are prepared by conventional
formulating techniques. Thus, typically, the foamable edible
anhydrous liquid oil and the foaming agent are mixed together along
with any other soluble ingredients of the composition. The solid to
be dispersed is then added, and the resultant mixture passes
through an appropriate mill to ensure uniform particle size. The
batch is then submitted for aerosol filling into an aerosol can. An
aerosol valve is placed on the can and crimped onto the can. The
food grade propellant is then added by pressure filling.
In addition to the essential ingredients of the foam, there may
also be incorporated in the foams of the present invention any of a
variety of additives or a combination thereof, commonly added to
aerosol compositions or to toiletries, cosmetics, or
pharmaceuticals. Typically, such additives are those such as
emollients, lubricants, humectants, abrasives, and perfumes. Thus,
the edible anhydrous aerosol foam of the present invention may be
used as a vehicle for any of a large variety of active
pharmaceutical materials or cosmetic ingredients. Additionally, the
foam itself can be used as a base for various sweetening and
flavoring agents in order to provide a food item.
EXAMPLES
In all of the following examples high levels of solids are
dispersed in oils and foamed with surfactant and propellant from
the aerosol can. All parts are by weight, unless otherwise
indicated.
Unless otherwise indicated, each formulation of the examples was
prepared according to the following general instructions: Heat the
oils, the surfactants, and any other oil-soluble ingredients
together to 60.degree. C..+-.5.degree. C. Then add the solids to
the oil phase with vigorous agitation to assure uniform dispersion
(5-15 minutes). After cooling to 40.degree. C..+-.5.degree. C., add
any flavors and mix well. Pass the composition through a
homogenizer or colloid mill to disperse agglomerates. Fill an
aerosol can with the composition and then crimp on a valve. Add the
propellant (e.g., propane) through the valve. Shake well to
dissolve the propellant in the system.
EXAMPLE I
Fish Oil Whip
______________________________________ Weight %
______________________________________ Fish Oil-30% Omega 3 fatty
acids (oil) 53.80 Octaglycerol monooleate (foamer) 4.00 Triglycerol
monooleate (foamer) 4.00 Sorbitan monostearate (foamer) 3.00
Cab-O-Sil M5 (anti-caking agent, 1.50 fumed SiO.sub.2, (dispersed
solids) Citric acid anhydrous USP (tartness) 0.15 Flavors
(oil-solubles) 0.55 Sugar 12X, N.F. (sweetener, 30.00 dispersed
solids) Propane (propellant) 3.00 100.00
______________________________________
This system masks the taste of the fish oil and stabilizes the oil
against rancidification due to air oxidation or microbial attack.
Each five gram spoonful of the delicious whip delivers about three
grams of fish oil, equivalent to taking three large
difficult-to-swallow soft gelatin capsules.
EXAMPLE II
Cod Liver Oil Whip
______________________________________ Weight %
______________________________________ Cod liver oil USP 44.80
Decaglycerol tetraoleate 6.00 Sorbitan monostearate 2.00 Glyceryl
monostearate 2.00 Sugar 12X, N.F. 40.00 Citric acid 0.15 Cab-O-Sil
M5 1.50 Flavors 0.55 Propane 3.00 100.00
______________________________________
The formulation effectively masks the taste and odor of cod liver
oil and provides a palatable cream whip form for the administration
of this natural source of vitamins A and D, particularly to
children.
EXAMPLE III
Chocolate Dessert Foam Topping
______________________________________ Weight %
______________________________________ Lecithin, granular 5.00
Sugar, 12X, N.F. 20.00 Bakers chocolate (dispersed solid) 4.00
Glyceryl monostearate 2.50 Vanillin (dispersed solid) 0.25 Flavor
0.40 Soybean oil 64.85 Propane 3.00 100.00
______________________________________
This system delivers a delicious chocolate topping for ice cream
cakes and for other desserts. As it requires no refrigeration, it
can be kept in convenient locations in the kitchen or dining
room.
EXAMPLE IV
Mineral Oil Laxative Foam
______________________________________ Weight %
______________________________________ Heavy mineral oil, USP 55.2
Sugar 12X, N.F. 30.0 Cab-O-Sil M5 3.0 Veegum F (absorbent, 2.0
dispersed solid) Triglycerol monostearate 3.0 Sorbitan monostearate
3.5 Citric acid anhydrous USP 0.1 Orange flavor 0.2 Propane 3.0
100.00 ______________________________________
One ounce of whip provides a laxative dose of mineral oil for
adults in a very pleasant, non-greasy, easy-to-take form.
EXAMPLE V
Chocolate Mousse Topping
______________________________________ Weight %
______________________________________ Decaglycerol tetraoleate 6.0
Lecithin 2.0 Sorbitan monostearate 2.0 Soybean oil 50.4 Sugar 12X
N.F. 25.0 Cocoa, powdered (dispersed solids) 10.0 Cab-O-Sil M5 1.0
Artificial chocolate flavor (oil-soluble) 0.6 Propane 3.0 100.0
______________________________________
This whip can be used as a cake frosting or topping for desserts.
The aerosol form facilitates spreading. No refrigeration is
required.
EXAMPLE VI
Coffee Creamer
______________________________________ Weight %
______________________________________ Powdered nonfat milk
(dispersed solids) 20.0 Octaglycerol monooleate 7.0 Sorbitan
monostearate 2.0 Cab-O-Sil M5 1.0 Titanium dioxide (dispersed
solids) 1.0 Mono and diglycerides of fatty acids (oils) 5.0 Flavors
0.5 Soybean oil 59.5 Propane 4.0 100.0
______________________________________
This milk-containing coffee creamer tastes as good as cream and
requires no refrigeration. It creates "instant cappucchino" with
push-button ease.
EXAMPLE VII
Castor Oil Whip
______________________________________ Weight %
______________________________________ Castor oil, USP 56.30 Sugar
12X, N.F. 30.00 Decaglycerol monooleate 6.00 Sorbitan monostearate
2.00 Cab-O-Sil M5 1.00 Citric acid, anhydrous USP 0.15 Flavors 0.55
Propane 4.00 100.00 ______________________________________
This good tasting foam makes it easier and more convenient for the
patient to ingest the large quantity of castor oil required for
intestinal purging prior to colonic X-rays or other diagnostic
testing.
EXAMPLE VIII
Vitamin E Whip
______________________________________ Weight %
______________________________________ Vitamin E (Alpha tocopherol)
0.1 1,000,000 IU per gram (oil soluble) Soybean Oil 44.6 Sugar 12X,
N.F. 40.00 Octaglycerol monooleate 4.0 Triglycerol monooleate 4.0
Sorbitan monostearate 3.0 Cab-O-Sil M5 1.0 Flavors 0.3 Propane 3.0
100.0 ______________________________________
Each gram of whip contains 1,000 IU Vitamin E
Large doses of oil-soluble vitamins can be easily administered in
whip form without requiring the swallowing of large capsules. Other
vitamins or other nutritional supplements like lecithin can be
added easily to the system. The stability of all these ingredients
is assured by the inert atmosphere and the hermetic seal of the
aerosol form.
EXAMPLE IX
Dyclonine Sore Throat Whip
______________________________________ Weight %
______________________________________ Dyclonine, base
(oil-soluble) 0.1 Menthol 0.2 Sugar 12X, N.F. 30.0 Cab-O-Sil M5 1.5
Flavors 0.3 Soybean oil 56.4 Decaglycerol tetraoleate 6.0 Sorbitan
monostearate 3.0 Propane 3.0 100.0
______________________________________
When local anesthetics like dyclonine are administered in whip
form, they coat the back of the throat providing long lasting pain
relief with minimal numbing of the mouth and tongue. This is in
contrast to the general mouth-numbing effect produced by anesthetic
lozenges or sprays.
EXAMPLE X
Phenylpropanolamine Whip
______________________________________ Weight %
______________________________________ Phenylpropanolamine, base
(oil-soluble) 0.8 Sugar 12X, N.F. 25.0 Veegum F 2.0 Cab-O-Sil M5
1.0 Decaglycerol tetraoleate 6.0 Sorbitan monostearate 4.0 Soybean
oil 58.2 Propane 3.0 100.0
______________________________________
Each 3 gram dose contains 25 mg of phenylpropanolamine.
Amine bases like phenylpropanolamine are soluble in the oil system
and can be reliably and accurately administered by means of a
metered valve. In this system the clay (Veegum F) is used to
complex with the drug and eliminate its bitter taste.
EXAMPLE XI
Chocolate Mousse Foam Food Topping
______________________________________ Weight %
______________________________________ Lecithin, granular 5.00
Sugar, fine powder 10X 20.00 Bakers chocolate 4.00 Glycerol
monostearate 2.50 Vanillin 0.25 Flavor 0.40 Soybean oil 64.85
Propane 3.00 100.00% ______________________________________
Procedure:
The lecithin, glycerol monostearate, and soybean oil are heated to
150.degree. F. until clear and uniform. The vanillin and Bakers
chocolate are mixed in, and the batch cooled to room temperature.
The sugar and flavor are added, and the entire batch passed through
a suitable mill to ensure particle uniformity. The batch is then
submitted for aerosol filling. Because the sugar is suspended in
the batch, the aerosol can must be shaken before use. When the
contents are used, a good tasting whipped cream-like foam is
formed.
EXAMPLE XII
Hot Oil Anti-Dandruff Mousse
______________________________________ Weight %
______________________________________ Valfor 950(anhydrous sodium
aluminosilicate) 35.00 Cab-O-Sil M5 1.00 Sorbitan monostearate 4.00
Polyethylene glycol 400 dioleate 2.00 Soybean oil, partially
hydrogenated 52.50 Fragrance 0.50 Propane 5.00 100.0
______________________________________
When this foam is applied to the wet hair and scalp, heat is
generated as a result of the exothermic reaction between Valfor 950
and water. The heat promotes the penetration of the oils into the
dandruff layers on the scalp, aiding in their removal by subsequent
rinsing. The foam is ingestible and palatable, although not
particularly appetizing.
It will be apparent to those skilled in the art that many
modifications, both of materials and methods, may be practiced
without departing from the purpose and intent of the
disclosure.
* * * * *